Find 1/(sin 45 sin 46) + 1/(sin 47 sin 48) + ... + 1/(sin 133 sin 144).

Ok so i cant help srry

Find 1/(sin 45 sin 46) + 1/(sin 47 sin 48) + ... + 1/(sin 133 sin 144).

\(=\frac{1}{ (sin 45 sin 46)} + \frac{1}{(sin 47 sin 48) }+ ..         . + \frac{1}{sin (180-133) sin (180-144))}\\ =\frac{1}{ (sin 45 sin 46)} + \frac{1}{(sin 47 sin 48) }+ ..         . + \frac{1}{sin (47) sin (46))}\\ =\frac{1}{ sin 45 sin 46} + \frac{1}{sin 46sin 47} + \frac{1}{sin 47 sin 48 }.....+ \frac{1}{sin89sin90}\\ \)

Yea, I know, that does not help much.

sumfor(n, 45, 144, 1 / (sin n * sin (n+1))) = -1.511943134.....

∑[1/ [sin(n)*sin(n+1)], n, 45, 144] =-1.511943134.........